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P38 won't start: Fuel problem?


Andyl

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Having left the P38 for a couple of weeks, it had a flat battery, charged it up and refitted, once I'd fought my way through the key code lockout, the car still won't start!

The car cranks OK, but won't start, not a cough or splutter.

There's a valve on the fuel rail that looks very much like a tyre valve, I'd guess it's there to check fuel pressure. Don't know what that should be, but if I press the pin in I get a smell of petrol and no more, even with the ignition on. I've checked the fuse (39) and visually checked the relay (yeah, it's there and doesn't look burnt or melted!). So is this a fuel problem or am I missing something?

And what to check next ?

Andy

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Don't know the 3.9 well but if it helps the 3.5 pump only runs during cranking and when the flapper MAF is open so if I want to check my pump I have to hold the flapper open with the ignition on. I think the 3.9 does a couple of seconds of pump prime when the ignition is first turned on but again I'm not sure.

You need a helper (to turn the key to crank) so that you can listen to the relay to ensure it is moving (notice I avoided saying 'working'). If it sounds OK then slide under the back and listen for the pump when your helper again tries to crank.

My 3.5 went through a spell of the pump not starting until the tank had been abused with a heavy shoe. Inevitably this method did not last and the pump had to be replaced.

Steve

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Firstly, remember the fuel pump is ECU controlled so just because it doesn't run doesn't mean there's anything wrong with it - it could mean the ECU just isn't turning it on because it doesn't see the correct conditions to make the car run. You could still be "locked out" or there could be some other fault. or it could be the fuel pump after all. :unsure:

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Thanks.

There are just so many "black boxes" that could be the problem, I'm trying to make sure it IS fuel, before I spend a week chasing down something irrelevant! I have disconnected and reconnected the battery again in case something in the unlock/disarm process didn't clear properly last time.

It's a 4.6 P38, so I think the fuel rail should be pressurised with the ignition on position 2, but I'll get a helper to crank it while I check the above, it's a start!

Then i guess I might have to call for a tow to the man with the right computer. :(

Ta.

Andy

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  • 2 weeks later...

OK, so that was the fuel system relay. Changed that, started OK.

Next day I moved it a short distance and when I took the key out the engine didn't stop for a few seconds!

When it did stop I heard a buzzing noise still coming from under the bonnet and the fuel light was still on for the LPG. Tried turning on/off, lock/unlock, etc. Opened the bonnet and found that a relay (the main ignition relay I think) was buzzing furiously.

Replaced that, battery was then flat so couldn't try it. Strangely the wipers were in the middle of the screen and I don't remember it raining when I moved it.

Charged and reconnected battery - key code lock out leave it for 1/2 hour...

Then someone mentioned to me that the windscreen wipers were going. Car locked, key in my pocket, wipers weren't going when I left it.

sure enough, they were going. Wiper switch off, ignition off, car locked and wipers started themselves up on their own!

Couldn't find a wiper fuse, so removed both wiper relays and they stopped.

Is my car cursed or is there something in / under the engine bay fuse box that can do this kind of thing?

It could be the famous P38 electrical gremlin sitting in the engine bay chewing wires at random!

Oh why did I ever buy a P38! should have stuck with a classic, at least rust is predictable!

Help!

Cheers,

Andy

(Slightly desperate and a little more disheartened)

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Have you found the site www.rangerovers.net?

This site is THE world authority on the 38A, learn to like it, find your way around it.

I'd suggest starting with the main site, (this will take several hours), then move onto the 4.0/4.6/P38A forum off the front page.

If you have electric front seats, raise them to the highest position before disconnecting the electrics.

Wind the drivers window fully open before disconnecting the electrics.

NEVER leave the key in the ignition.

I'd suggest the wipers running could be the BECM faulty, but I suggest you also check for damp affecting wiring and connectors. In particular lift the carpet in the RH footwell and check the underfelt for damp, and the wiing there for swollen areas caused by corrosion.

Pull the plugs on the BECM and check for corrosion. You may eventually have to remove the BECM, open it, and look for overheating damage.

Lift the all the relays from the Engine Bay fuse box and check for signs of overheating where they plug into the base.

Unbolt the fuse box, remove the wiring connection plugs and look for corrosion or overheating.

HTH

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  • 16 years later...
On 3/29/2008 at 5:07 PM, Andyl said:

Having left the P38 for a couple of weeks, it had a flat battery, charged it up and refitted, once I'd fought my way through the key code lockout, the car still won't start!

The car cranks OK, but won't start, not a cough or splutter.

There's a valve on the fuel rail that looks very much like a tyre valve, I'd guess it's there to check fuel pressure. Don't know what that should be, but if I press the pin in I get a smell of petrol and no more, even with the ignition on. I've checked the fuse (39) and visually checked the relay (yeah, it's there and doesn't look burnt or melted!). So is this a fuel problem or am I missing something?

And what to check next ?

Andy

I have exactly the same problem, car was working fine, had a flat battery after being parked for a year, it tried to start after recoding with key, but now nothing, turns over freely but no smoke and the plugs are dry, changed the plugs anyway, and put on a new battery, and checked the fuel pump relay, seems ok, jumped the pump relay and i can hear it running, yet still wont run. I'm wondering if its the frigging immobiliser up to its old tricks again, not turning on the injectors. May try re-entering the code into the drivers door and see if that works, I just find this car so infuriating as you never know what to look for, other cars I've fixed myself, but this car has almost always been take to your main dealer

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The last thing you want to do is take a P38 to a main dealer. They're to be of interest to them and chances someone there actually knows the P38 and cares enough to work on one are slim to none. Your best bet is an independent with some experience.

But first have a proper and methodical look yourself. And to help us help you, what year is your car? There are some differences between pre and post '99.

- do you get any error messages (like engine disabled)? If not, unlikely to be the immobiliser
- have you checked the inertia switch?
- if you jump the fuel pump relay, is fuel actually getting to the engine? Push the schrader valve on the rail or better still, put a pressure gauge on it.
- do you have spark?
- have you tried starting with the jumper for the fuel pump relay?

Filip

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2 hours ago, Escape said:

The last thing you want to do is take a P38 to a main dealer. They're to be of interest to them and chances someone there actually knows the P38 and cares enough to work on one are slim to none. Your best bet is an independent with some experience. ,,,

Filip

"They're to be of interest to them".
What I think Filip meant to say is that the P38A will be of NO interest to a main dealer, for the reasons written or implied.

Regards.

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